I am not a fan of Grout Boost! I am remodeling my bath and made a rather large shower. The walls are 1x2 glass, approx. 130 sq. Ft. with travertine in the niches and 1x1 travertine on the floor.

I am using tec accucolor unsanded pearl colored grout mixed with grout boost. I followed the directions for mixing and the grout was about the consistency of peanut butter. I did about 5 pounds of grout per batch and it was about 30-45 minutes after application that I did the wiping with a sponge - wrung out as much as I possibly could.

The grout dried off-white, not the putty color, the pearl was supposed to be. It is a nice uniform color, so I don't think I washed too wet - even the grout that fell on the floor and wasn't washed at all dried the same color.

I don't know what I could have done differently to avoid efflorescence... I called grout boost tech support and they recommended an acid wash with 1 part vinegar, 1 part water. However I mentioned that the floor of the shower is travertine and they said to use a high alkaline cleaner instead. Either way I'm back to scrubbing grout joints around the approx. 9,000 tiles I have on the wall

The whole reason I used the grout boost was so I wouldn't have to apply sealer to all of those grout joints!! I'm very unhappy right now. Anyway, I'm wondering if anyone has any advice. I haven't grouted one wall of the shower or the floor yet. I plan on enhancing the floor with sealer/enhancer after grouting. Will the vinegar solution harm the floor tiles after sealing? Will any of this damage the glass tile? Anybody want to come help me scrub 3/32" grout joints? Ugh....

Also, I'm not sure if this is the correct sub-forum or if this should be posted in the general forum. Feel free to move it. Thanks!

I told the guy at Grout Boost or whatever their company's name is that it was a nice uniform color, but he said it still sounded like efflorescence???

So now I'm wondering, if it isn't, what about the color-matched caulk that I bought for the corners? Will it only match when the shower is wet and when it is dry it will look funny?

I'm thinking about trying the vinegar and water scrubbing on the sample tiles to see if it makes a difference. I tried lightly washing them with the vinegar/water solution last night, but didn't know you needed to let it soak in and then scrub it with a stiff brush.

I tried washing my sample board with vinegar/water. I just scrubbed it with a toothbrush since I don't know where my little stiff bristle brush is. It didn't seem to do anything. If it takes more elbow grease than that I'm not willing to do it on the whole shower anyway.

-Jason
I don't think the color looks bad, on the contrary, I think it looks better against the glass tile anyway. I wanted to know if this was normal efflorescence before I did all of the walls in case I could easily fix it and maybe change the technique on the remaining walls so it didn't happen again. And I made a sample board mainly to test sanded vs. non-sanded since I'm mixing glass and tumbled trav. and to test the effect of sealing before or after grouting.

-CX
I think you may be right. I've done some searches and it seems I'm not the first to get pretty dramatic lighter color, efflorescence or other issues with grout boost. The guy wasn't really listening to what I had to say so I didn't waste much time on him - I've got a master bathroom to finish and I'm getting tired of sleeping in the same room as my 3 month old!

-doitright
Thanks for the compliment. I'm happy that it is an even color and if it is some weird grout boost-specific efflorescence at least it's uniform and I can live with that.

I'm still curious what you guys would do for caulking in the corners. I bought the color matched caulk, but I'm pretty sure it won't match now unless it's wet. However, grout boost says you are supposed to wait 10 days before getting it wet so maybe I'll wait and see if anything changes after 10 days. If all grout gets darker when wet are most showers grout and caulk not the same color depending on whether it's wet or dry? I'm assuming that the caulk won't get darker when wet...

Personally, I use silicone caulk in all wet areas. My favorites are TEC, Laticrete, and Color Rite when I need a custom match from any grout manufacturer. Color Rite silicone (Colorsil and Polysil) now have a textured silicone and a matte finish silicone.

__________________
John Koessler

"The bitterness of poor quality remains long after the sweetness of a low price is forgotten."

I bought 4 tubes of the TEC silicone caulk when I bought the grout. I don't know that I could bring it back and exchange it for a different color since I bought it a few months ago - I was hoping to have this done before the new baby arrived...

I'm thinking about trying the same grout on the floor of the shower (and on my sample first) without the grout boost to see what color it ends up. So I may use that caulk on the floor-to-wall joints. I'm tempted to just grout the wall corners, but since I used those 1x2 tiles and the corners weren't quite square the gap got a little big (1/4") so the non-sanded grout would most likely crack I'd guess...